Tree Style Tab - Tree Style Tab is an all-in-one Firefox extension that provides ability in order to operate tabs as a tree.

Parallel Space - Parallel Space – Multiple accounts and Two-Face is free to use mobile app that helps you clone or run multiple accounts of the same app simultaneously, and use themes to style your unique space.

OneTab - Whenever you find yourself with too many tabs, click the OneTab icon to convert all of your tabs into a list. When you need to access the tabs again, you can either restore them individually or all at once.

App Cloner - Clone your Android apps so you can use multiple logins.

Firefox Multi-account Containers - Sign in to two different accounts on the same site

2Accounts - 2Accounts is an up-to-the-mark tool that enables its global users to enjoy multiple accounts for messaging, multi-gaming, and run a double social account for work and personal life.